#include <iostream>
#include "head.h"

using namespace std;

int main()
{
    int a = 10,b = 20;
    cout << "a = "<< a <<" , b = "<< b<<endl;
    cout << "a + b = " << add(a,b) << endl;
    cout << "a - b = " << sub(a,b) << endl;
    cout << "a * b = " << mul(a,b) << endl;
    cout <<" a / b = " << divide(a,b) << endl;
    return 0;
}